M2M (Machine to Machine) communication technology has come into the spotlight with the advent of ubiquitous era. M2M can be used for various applications such as e-health, smart grid, smart home, etc. In such applications, M2M devices having various hardware specifications are used and thus a protocol which can accept any type of M2M device is needed. Accordingly, it is necessary to develop an application layer protocol suitable for resource-constrained M2M devices. Such protocol is applicable to resource-constrained M2M devices and thus can also be applied to M2M devices having different specifications.
In the meantime, M2M devices require access control technology. Particularly, when an M2M server account registered with an M2M client is deleted, it is necessary to process M2M server account deletion and resources associated with an M2M server to be deleted. According to M2M server account deletion, a specific resource may be a resource for which access rights are not present or an M2M server that manages access rights for resources in an M2M client may be removed. Accordingly, a solution thereto is needed.